Removal of emulsified oil with organic coagulants and dissolved air flotation (DAF)
- Carnegie-Mellon Univ.
Laboratory and pilot-plant studies were conducted on the removal of emulsified oil from refinery wastewater by DAF, e.g., to evaluate the use of organic surface active agents and polyelectrolytes as coagulants. The best polyelectrolyte was 75% charged polydiallyldimethylammonium compound cationic polyelectrolyte WT 2640 in pH range 7.0-8.5. The optimum dose, 15 mg/l., was independent of emulsified oil concentration or composition in the range 200-2000 mg/l. WT 2640 performed reliably under a wide variety of input conditions with DAF effluent oil concentrations averaging 10 mg/l. The concentration of oil in the DAF scum was on the order of 50% by wt and the removed oil was easily scraped from the surface of the air flotation chamber. The use of polyelectrolytes seems to be economically promising if the oil recovered can be reprocessed in the refinery. Preliminary results showed that the quickest capture of oil droplets by an air bubble occurred when the rate of oil droplet coagulation was most rapid, i.e., the point of zero net charge in the oil droplets. Thus, good coagulation also means good removal of oil in the DAF process.
- OSTI ID:
- 5054668
- Journal Information:
- J. - Water Pollut. Control Fed.; (United States), Vol. 50:2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Critical evaluation and modeling of algal harvesting using dissolved air flotation. DAF Algal Harvesting Modeling
Intensified flotation of finely emulsified oils from effluents
Related Subjects
PETROLEUM
RECOVERY
PETROLEUM REFINERIES
WASTE WATER
FLOTATION
FLOCCULATION
PILOT PLANTS
WATER POLLUTION CONTROL
CONTROL
ENERGY SOURCES
FOSSIL FUELS
FUELS
FUNCTIONAL MODELS
HYDROGEN COMPOUNDS
INDUSTRIAL PLANTS
LIQUID WASTES
OXYGEN COMPOUNDS
POLLUTION CONTROL
PRECIPITATION
SEPARATION PROCESSES
WASTES
WATER
020800* - Petroleum- Waste Management